asp.net web api - AutoFac with WebApi, Still looking for parameter less constructor -

i have following class in webapi project , registercontainer() method gets called global.asax class. injecting service in api controller. issue it;s throwing exception , not getting instantiated corrected. says no paremeterless controller found. idea what's wrong code

public class iocconfig {     #region public methods , operators      /// <summary>     ///     adds dependencies container     /// </summary>     /// <returns></returns>     public static void registercontainer()     {         var builder = new containerbuilder();          builder.registercontrollers(assembly.getexecutingassembly());         builder.registerapicontrollers(assembly.getexecutingassembly());         icontainer container = builder.build();         dependencyresolver.setresolver(new autofacdependencyresolver(container));         globalconfiguration.configuration.dependencyresolver = new autofacwebapidependencyresolver(container);         registermodules(builder);         registercontrollers(builder);     }      #endregion      #region methods      private static void registercontrollers(containerbuilder builder)     {         builder.registerapicontrollers(assembly.getexecutingassembly());     }      private static void registerdependencyresolver(icontainer container, containerbuilder builder)     {         idependencyresolver resolver = new autofacwebapidependencyresolver(container);          dependencyresolver.setresolver(resolver);     }      private static void registermodules(containerbuilder builder)     {          builder.registermodule(new domainmodule());         builder.registermodule(new repositorymodule());         builder.registermodule(new servicefacademodule());         builder.registermodule(new mappingmodule());      }      #endregion } 

}

update:

i have changed , added following lines global.asax.

protected void application_start()     {         arearegistration.registerallareas();         globalconfiguration.configure(webapiconfig.register);         filterconfig.registerglobalfilters(globalfilters.filters);         routeconfig.registerroutes(routetable.routes);         bundleconfig.registerbundles(bundletable.bundles);         //iocconfig.registercontainer();         //webapiconfig.register(globalconfiguration.configuration);          var builder = new autofac.containerbuilder();         builder.registercontrollers(typeof(webapiapplication).assembly).propertiesautowired();         builder.registermodule(new repositorymodule());         builder.registermodule(new servicefacademodule());         builder.registermodule(new repositorymodule());         builder.registermodule(new mappingmodule());         builder.registermodule(new domainmodule());         var container = builder.build();         dependencyresolver.setresolver(new autofacdependencyresolver(container));       } 

you trying register modules after container has built.

you need move call

registermodules(builder); 

before create container builder.build():

registermodules(builder); icontainer container = builder.build(); 

in updated code missing 2 things now:

• registering api controllers registerapicontrollers
• setting autofacwebapidependencyresolver

so code should like:

var builder = new autofac.containerbuilder(); builder.registercontrollers(typeof(webapiapplication).assembly).propertiesautowired(); builder.registerapicontrollers(typeof(webapiapplication).assembly).propertiesautowired(); builder.registermodule(new repositorymodule()); builder.registermodule(new servicefacademodule()); builder.registermodule(new repositorymodule()); builder.registermodule(new mappingmodule()); builder.registermodule(new domainmodule()); var container = builder.build(); dependencyresolver.setresolver(new autofacdependencyresolver(container)); globalconfiguration.configuration.dependencyresolver = new autofacwebapidependencyresolver(container);